Book Image

Hands-On Reinforcement Learning for Games

By : Micheal Lanham
Book Image

Hands-On Reinforcement Learning for Games

By: Micheal Lanham

Overview of this book

With the increased presence of AI in the gaming industry, developers are challenged to create highly responsive and adaptive games by integrating artificial intelligence into their projects. This book is your guide to learning how various reinforcement learning techniques and algorithms play an important role in game development with Python. Starting with the basics, this book will help you build a strong foundation in reinforcement learning for game development. Each chapter will assist you in implementing different reinforcement learning techniques, such as Markov decision processes (MDPs), Q-learning, actor-critic methods, SARSA, and deterministic policy gradient algorithms, to build logical self-learning agents. Learning these techniques will enhance your game development skills and add a variety of features to improve your game agent’s productivity. As you advance, you’ll understand how deep reinforcement learning (DRL) techniques can be used to devise strategies to help agents learn from their actions and build engaging games. By the end of this book, you’ll be ready to apply reinforcement learning techniques to build a variety of projects and contribute to open source applications.
Table of Contents (19 chapters)
1
Section 1: Exploring the Environment
7
Section 2: Exploiting the Knowledge
15
Section 3: Reward Yourself

Applying TDL to Q-learning

Q-learning is considered one of the most popular and often used foundational RL methods . The method itself was developed by Chris Watkins in 1989 as part of his thesis, Learning from Delayed Rewards. Q-learning or rather Deep Q-learning, which we will cover in Chapter 6, Going Deep with DQN, became so popular because of its use by DeepMind (Google) to play classic Atari games better than a human. What Watkins did was show how an update could be applied across state-action pairs using a learning rate and discount factor gamma.

This improved the update equation into a Q or quality of state-action update equation, as shown in the following formula:

In the previous equation, we have the following:

  • The current state-action quality being updated
  • The learning rate
  • The reward for the next state
  • Gamma, the discount factor
  • Take the max best or greedy action...